Front pipe crush gasket

Could anybody tell me what size or where to get the gasket for the front pipe, it has a 3 bolt flange and a ball type fitting.  Cannot find it anywhere listed for the car.

I don't recall ever having a gasket, the ball part of the rear pipe fit snug into the down pipe and sealed well. When I upgraded the down pipe to an S13 type and replaced the rear pipe with 2.5 inch, the shop made a good fit there also.

Thanks for the help.  When I took it off I noticed there was no gasket and my shop manual did not have one detailed in the drawing.  I just wanted to be sure as I ordered every other gasket on the exhaust side in order to stop my car from sounding like a volkswagen.